Catalyst activator

ABSTRACT

A catalyst activator particularly adapted for use in the activation of metal complexes of metals of Group 3-10 for polymerization of ethylenically unsaturated polymerizable monomers, especially olefins, comprising two Group 13 metal or metalloid atoms and a ligand structure including at least one bridging group connecting ligands on the two Group 13 metal or metalloid atoms.

CROSS REFERENCE TO RELATED APPLICATION

This application claims benefit of priority under 35 U.S.C. §371 ofPCT/US98/14106, filed Jul. 7, 1998, which published under PCT Article21(2) in the English language and which claims benefit of priority ofprovisional application No. 60/054,586, filed Aug. 1, 1997.

STATEMENT OF GOVERNMENTAL RIGHTS

The United States of America through the Department of Energy, islicensed to practice under the claims of this patent by means of DOEGrant No. DE-FG02-86ER13511.

The present invention relates to compounds that are useful as catalystcomponents. More particularly the present invention relates to suchcompounds that are particularly adapted for use in the coordinationpolymerization of unsaturated compounds comprising two Group 13 metal ormetalloid atoms and a ligand structure including at least one bridginggroup connecting ligands on two Group 13 metal or metalloid atomsthereof. Such compounds are particularly advantageous for use in apolymerization process wherein catalyst, catalyst activator, and atleast one polymerizable monomer are combined under polymerizationconditions to form a polymeric product.

It is previously known in the art to activate Ziegler-Nattapolymerization catalysts, particularly such catalysts comprising Group3-10 metal complexes containing delocalized π-bonded ligand groups, bythe use of Bronsted acid salts capable of transferring a proton to forma cationic derivative or other catalytically active derivative of suchGroup 3-10 metal complex. Preferred Bronsted acid salts are suchcompounds containing a cation/anion pair that are capable of renderingthe Group 3-10 metal complex catalytically active. Suitable activatorscomprise fluorinated arylborate anions, most preferably, thetetrakis(pentafluorophenyl)borate anion. Additional suitable anionsinclude sterically shielded diboron anions of the formula:

wherein:

S is hydrogen, alkyl, fluoroalkyl, aryl, or fluoroaryl, Ar^(F) isfluoroaryl, and X¹ is either hydrogen or halide, disclosed in U.S. Pat.No. 5,447,895. Additional examples include carborane compounds such asare disclosed and claimed in U.S. Pat. No. 5,407,884.

Additional bisborane compounds lacking in aromatic bridging groups havebeen previously disclosed in U.S. Pat. No. 5,496,960, Angew. Chem. Int.Ed. Engl., (1995) 34(7), 809-11, Polyhedron, (1997), 17(1), 119-124,Organometallics, (1994), 13(10) 3755-7, Aust. J. Chem. (1979), 32(11),2381-93 and Spectrochim, ACTA, PART A, (1968), 24(8), 1125-33.

Examples of preferred charge separated (cation/anion pair) activatorsare protonated ammonium, sulfonium, or phosphonium salts capable oftransferring a hydrogen ion, disclosed in U.S. Pat. No. 5,198,401, U.S.Pat. No. 5,132,380, U.S. Pat. No. 5,470,927, and U.S. Pat. No.5,153,157, as well as oxidizing salts such as carbonium, ferrocenium andsilyilium salts, disclosed in U.S. Pat. No. 5,350,723, U.S. Pat. No.5,189,192 and U.S. Pat. No. 5,626,087.

Further suitable activators for the above metal complexes include strongLewis acids including (trisperfluorophenyl)borane andtris(perfluorobiphenyl)borane. The former composition has beenpreviously disclosed for the above stated end use in EP-A-520,732,whereas the latter composition is similarly disclosed by Marks, et al.,in J. Am. Chem. Soc., 118, 12451-12452 (1996).

Despite the satisfactory performance of the foregoing catalystactivators under a variety of polymerization conditions, there is stilla need for improved cocatalysts for use in the activation of variousmetal complexes under a variety of reaction conditions. Accordingly, itwould be desirable if there were provided compounds that could beemployed in solution, slurry, gas phase or high pressure polymerizationsand under homogeneous or heterogeneous process conditions havingimproved activation properties.

According to the present invention there is now provided Group 13containing compounds useful as catalyst activators in neutral (Lewisacid) or charge separated (cation/anion pair) form, corresponding to theformula:

wherein:

B¹ and B² independently each occurrence are Group 13 metal or metalloidatoms, preferably boron;

Z* is an optional divalent bridging group containing from 1 to 20 atoms,not counting hydrogen atoms;

R¹ and R² independently each occurrence are monovalent, anionic ligandgroups containing from 1 to 40 atoms not counting hydrogen atoms, and,for cationic compounds, additionally comprising a dissociated cationmoiety;

Ar^(f1) and Ar^(f2) independently each occurrence are monovalent,fluorinated organic groups containing from 6 to 100 carbon atoms,optionally, an Ar^(f1) and an R² group, or an Ar^(f2) and an R¹ grouptogether form a divalent bridging group, and further optionally anAr^(f1) group and an Ar^(f2) group together form a C₆₋₁₀₀ divalentbridging group,

z is 0 or 1,

r and s independently are 0, 1 or 2, and

m and n are 1, 2 or 3;

with the proviso that when z is 0, at least one of Ar^(f1) and Ar^(f2)are joined together, and the sum of r, z and m is 3 or 4, in the formerevent B¹ is neutral and in the latter event B¹ is negatively charged,said charge being balanced by a cation component of one R¹; and the sumof s, z and n is 3 or 4, in the former event B² is neutral and in thelatter event B² is negatively charged, said charge being balanced by acation component of one R².

Additionally according to the present invention there is provided acatalyst composition for polymerization of an ethylenically unsaturated,polymerizable monomer comprising, in combination, the above describedcompound and a Group 3-10 metal complex, or the reaction product of suchcombination.

Additionally according to the present invention there is provided aprocess for polymerization of one or more ethylenically unsaturated,polymerizable monomers comprising contacting the same, optionally in thepresence of an inert aliphatic, alicyclic or aromatic hydrocarbon, withthe above catalyst composition.

The foregoing compounds are uniquely adapted for use in activation of avariety of metal complexes, especially Group 4 metal complexes, understandard and atypical olefin polymerization conditions. They areuniquely capable of forming monomeric and dimeric cationic metalcomplexes when combined with neutral metallocene complexes under suchpolymerization conditions. Because of this fact, the foregoing compoundsare capable of forming highly desirable olefin polymers having enhancedlevels of long chain branching, stereospecificity and comonomerdistribution. In particular, bis-anions, due to the pairing of activecatalyst sites in close proximity to one another, are capable ofproviding a higher local concentration of active catalyst site at thepoint of polymer formation. Moreover, such paired catalyst sites may becomprised of two disparate metals or metal ligand arrangements, orotherwise tailored to provide desirable polymer properties. For example,the use of symmetrical or unsymmetrical bis-anions results in twocatalytically active sites that are held in close proximity during apolymerization reaction, thereby providing a large increase in localconcentration of active catalyst sites. This increased localconcentration of active catalyst sites leads to enhanced polymerstereostructure, molecular weight and microstructure. Certain catalystsites in close proximity result in random comonomer incorporation,others affect the stereospecificity of their close neighbor. Bycontrolling the random versus clustered distribution of comonomer,blocky or non-blocky copolymers can be prepared. Additionally, the twocatalysts associated with each bis-anion may themselves be nonspecificor stereospecific, such that the resulting combination catalyst isadapted to produce block copolymers via polymer interchange between suchnonspecific and stereospecific catalysts. The degree of long-chainbranching in polyolefins produced using multiple catalyst sites onbis-anions is enhanced due to the rate of reincorporation of in situgenerated vinyl terminated macromonomer into the growing polymer chaindue to the higher local concentration of catalyst.

DETAILED DESCRIPTION OF THE INVENTION

All references herein to elements belonging to a certain Group refer tothe Periodic Table of the Elements published and copyrighted by CRCPress, Inc., 1995. Also any reference to the Group or Groups shall be tothe Group or Groups as reflected in this Periodic Table of the Elementsusing the IUPAC system for numbering groups. When, in reference to acation portion of any compound herein, it is stated that a ligand groupcomprises such cation, it is to be understood that the cation is notchemically or physically incorporated in said ligand, or necessarilychemically attached thereto, in as much as the cation may freelydissociate from the anion portion of the compound. Rather, such ligandgroup is said to “comprise” the cation in order to properly account forthe correct number of cations as dictated by considerations of chargebalance.

The catalyst activators of the invention are further characterized inthe following manner. Preferred Group 13 metal or metalloids includealuminum and boron. Most highly preferably, both B¹ and B² are boron.The cocatalysts may be neutral Lewis acids or salts comprising one ormore cation-anion pairs. Examples of suitable neutral Lewis acidsaccording to the present invention correspond to the formula:

wherein all variables are as previously defined, and the sum of r, z andm and the sum of s, z and n are both 3.

More specific examples of the foregoing Lewis acid compounds correspondto the formula:

wherein:

R¹ and R² independently each occurrence are C₁₋₂₀ hydrocarbyl,halohydrocarbyl, or halocarbyl, and

Ar^(f1)-Ar^(f2) in combination, independently each occurrence, is adivalent fluoro-substituted aromatic group of from 6 to 20 carbons.

Preferred examples of the foregoing Lewis acid compounds are thefollowing:

Examples of suitable charge separated compounds according to the presentinvention correspond to the formula:

wherein:

R¹ and R² independently each occurrence are C₁₋₂₀ hydrocarbyl,halohydrocarbyl, or halocarbyl groups, and (when the sum of r, z and mis 4) one R¹ additionally comprises a cation selected from the groupconsisting of protonated cations of Bronsted acids, ferrocenium cations,carbonium cations, silylium cations, and Ag⁺, and (when the sum of s, zand n is 4) one R² additionally comprises a cation selected from thegroup consisting of protonated cations of Bronsted acids, ferroceniumcations, carbonium cations, silylium cations, and Ag⁺;

r and s are 0, 1 or 2 with the proviso that at least one of r or s isnot 0, and the sum of r, z and m is 3 or 4 and the sum of s, z and n is3 or 4, with the proviso that at least one of the foregoing sums is 4.

More specific examples of the foregoing charge separated compoundscorrespond to the formula:

wherein:

R¹ and R² independently each occurrence are C₁₋₂₀ hydrocarbyl,halohydrocarbyl, or halocarbyl groups, and (when connected to anegatively charged boron atom) one R¹ additionally comprises a cationselected from the group consisting of protonated cations of Bronstedacids, ferrocenium cations, carbonium cations, silylium cations, andAg⁺, and (when connected to a negatively charged boron atom) one R²additionally comprises a cation selected from the group consisting ofprotonated cations of Bronsted acids, ferrocenium, carbonium cations,silylium cations, and Ag⁺; and

an Ar^(f1) group and an Ar^(f2) group together form a C₆₋₂₀ divalentfluoro-substituted aromatic group of from 6 to 20 carbons.

Specific examples of the foregoing salt compounds are the following:

wherein, R is a C₁₋₄₀ hydrocarbyl ligand group, and L⁺ is a cation of aBronsted acid, or a ferrocenium, carbonium, silylium, or Ag⁺ cation.

More preferably L⁺ is an ammonium cation of the formula HN⁺R₃, wherein Ris C₁₋₅₀ hydrocarbyl. Most preferably, one or two R groups are C₁₄₋₅₀aliphatic groups, and the remaining R group(s) is (are) C₁₋₄ aliphatic.

The skilled artisan will appreciate that upon activation of a metalcomplex to a catalytically active state by the present compounds, to theextent a cationic derivative thereof is formed, the foregoing chargeseparated compounds may include therein the cationic derivative of suchmetal complex in place of the foregoing Bronsted acid, ferrocenium,carbonium, silylium, or Ag⁺ cations. For the preferred complexes themetal is selected from Groups 3-10 of the Periodic Table of theElements, more preferably Group 4. Accordingly, such cationic derivativewould be a Group 3-10 metal containing cation, more preferably a Group 4metal containing cation.

Generally, solubility of the compounds of the invention in aliphaticcompounds is increased by incorporation of one or more oleophilic groupssuch as long chain alkyl groups; long chain alkenyl groups; or halo-,alkoxy-, amino-, silyl-, or germyl-substituted long chain alkyl groupsor long chain alkenyl groups into the cation, L⁺. By the term “longchain” are meant groups having from 10 to 50 non-hydrogen atoms in suchgroup, preferably in a non-branched form. It is understood that thecompound may comprise a mixture of oleophilic groups of differinglengths in the cation. For example, one suitable compound comprises theprotonated ammonium salt derived from the commercially available longchain amine comprising a mixture of two C₁₄, C₁₆ or C₁₈ alkyl groups andone methyl group. Such amines are available from Witco Corp., under thetrade name Kemamine™ T9701, and from Akzo-Nobel under the trade nameArmeen™ M2HT.

Suitable catalysts for use in combination with the foregoing cocatalystsinclude any compound or complex of a metal of Groups 3-10 of thePeriodic Table of the Elements capable of being activated to polymerizeethylenically unsaturated compounds by the present activators. Examplesinclude Group 10 diimine derivatives corresponding to the formula:

M* is Ni(II) or Pd(II);

K is halo, hydrocarbyl, or hydrocarbyloxy;

Ar* is an aryl group, especially 2,6-diisopropylphenyl or aniline group;

CT—CT is 1,2-ethanediyl, 2,3-butanediyl, or form a fused ring systemwherein the two T groups together are a 1,8-naphthanediyl group; and

A⁻ is the anionic component of the foregoing charge separatedactivators.

Similar catalysts to the foregoing are also disclosed by M. Brookhart,et al., in J. Am. Chem. Soc., 118, 267-268(1996) and J. Am. Chem. Soc.,117, 6414-6415 (1995), as being active polymerization catalystsespecially for polymerization of α-olefins, either alone or incombination with polar comomoners such as vinyl chloride, alkylacrylates and alkyl methacrylates.

Additional catalysts include derivatives of Group 3, 4, or Lanthanidemetals which are in the +2, +3, or +4 formal oxidation state. Preferredcompounds include metal complexes containing from 1 to 3 π-bondedanionic or neutral ligand groups, which may be cyclic or non-cyclicdelocalized π-bonded anionic ligand groups. Exemplary of such π-bondedanionic ligand groups are conjugated or nonconjugated, cyclic ornon-cyclic dienyl groups, allyl groups, boratabenzene groups, and arenegroups. By the term “π-bonded” is meant that the ligand group is bondedto the transition metal by a sharing of electrons from a partiallydelocalized π-bond.

Each atom in the delocalized π-bonded group may independently besubstituted with a radical selected from the group consisting ofhydrogen, halogen, hydrocarbyl, halohydrocarbyl, hydrocarbyl-substitutedmetalloid radicals wherein the metalloid is selected from Group 14 ofthe Periodic Table of the Elements, and such hydrocarbyl- orhydrocarbyl-substituted metalloid radicals further substituted with aGroup 15 or 16 hetero atom containing moiety. Included within the term“hydrocarbyl” are C₁₋₂₀ straight, branched and cyclic alkyl radicals,C₆₋₂₀ aromatic radicals, C₇₋₂₀ alkyl-substituted aromatic radicals, andC₇₋₂₀ aryl-substituted alkyl radicals. In addition two or more suchradicals may together form a fused ring system, including partially orfully hydrogenated fused ring systems, or they may form a metallocyclewith the metal. Suitable hydrocarbyl-substituted organometalloidradicals include mono-, di- and tri-substituted organometalloid radicalsof Group 14 elements wherein each of the hydrocarbyl groups containsfrom 1 to 20 carbon atoms. Examples of suitable hydrocarbyl-substitutedorganometalloid radicals include trimethylsilyl, triethylsilyl,ethyidimethylsilyl, methyidiethylsilyl, triphenylgermyl, andtrimethylgermyl groups. Examples of Group 15 or 16 hetero atomcontaining moieties include amine, phosphine, ether or thioethermoieties or divalent derivatives thereof, e. g. amide, phosphide, etheror thioether groups bonded to the transition metal or Lanthanide metal,and bonded to the hydrocarbyl group or to the hydrocarbyl-substitutedmetalloid containing group.

Examples of suitable anionic, delocalized π-bonded groups includecyclopentadienyl, indenyl, fluorenyl, tetrahydroindenyl,tetrahydrofluorenyl, octahydrofluorenyl, pentadienyl, cyclohexadienyl,dihydroanthracenyl, hexahydroanthracenyl, decahydroanthracenyl groups,and boratabenzene groups, as well as C₁₋₁₀ hydrocarbyl-substituted orC₁₋₁₀ hydrocarbyl-substituted silyl substituted derivatives thereof.Preferred anionic delocalized π-bonded groups are cyclopentadienyl,pentamethylcyclopentadienyl, tetramethylcyclopentadienyl,tetramethylsilylcyclo-pentadienyl, indenyl, 2,3dimethylindenyl,fluorenyl, 2-methylindenyl, 2-methyl-4-phenylindenyl,tetrahydrofluorenyl, octahydrofluorenyl, and tetrahydroindenyl.

The boratabenzenes are anionic ligands which are boron containinganalogues to benzene. They are previously known in the art having beendescribed by G. Herberich, et al., in Organometallics, 14,1, 471-480(1995). Preferred boratabenzenes correspond to the formula:

wherein R″ is selected from the group consisting of hydrocarbyl, silyl,or germyl, said R″ having up to 20 non-hydrogen atoms. In complexesinvolving divalent derivatives of such delocalized π-bonded groups oneatom thereof is bonded by means of a covalent bond or a covalentlybonded divalent group to another atom of the complex thereby forming abridged system.

A suitable class of catalysts are transition metal complexescorresponding to the formula:

Lp_(l)MX_(m)X′_(n)X″_(p), or a dimer thereof

wherein:

Lp is an anionic, delocalized, π-bonded group that is bound to M,containing up to 50 non-hydrogen atoms, optionally two Lp groups may bejoined together forming a bridged structure, and further optionally oneLp may be bound to X;

M is a metal of Group 4 of the Periodic Table of the Elements in the +2,+3 or +4 formal oxidation state;

X is an optional, divalent substituent of up to 50 non-hydrogen atomsthat together with Lp forms a metallocycle with M;

X′ is an optional neutral ligand having up to 20 non-hydrogen atoms;

X″ each occurrence is a monovalent, anionic moiety having up to 40non-hydrogen atoms, optionally, two X″ groups may be covalently boundtogether forming a divalent dianionic moiety having both valences boundto M, or, optionally 2 X″ groups may be covalently bound together toform a neutral, conjugated or nonconjugated diene that is π-bonded to M(whereupon M is in the +2 oxidation state), or further optionally one ormore X″ and one or more X′ groups may be bonded together thereby forminga moiety that is both covalently bound to M and coordinated thereto bymeans of Lewis base functionality;

l is 0, 1 or 2;

m is 0 or 1;

n is a number from 0 to 3;

p is an integer from 0 to 3; and

the sum, l+m+p, is equal to the formal oxidation state of M, except when2 X″ groups together form a neutral conjugated or non-conjugated dienethat is π-bonded to M, in which case the sum l+m is equal to the formaloxidation state of M.

Preferred complexes include those containing either one or two Lpgroups. The latter complexes include those containing a bridging grouplinking the two Lp groups. Preferred bridging groups are thosecorresponding to the formula (ER*₂)_(x) wherein E is silicon, germanium,tin, or carbon, R* independently each occurrence is hydrogen or a groupselected from silyl, hydrocarbyl, hydrocarbyloxy and combinationsthereof, said R* having up to 30 carbon or silicon atoms, and x is 1 to8. Preferably, R* independently each occurrence is methyl, ethyl,propyl, benzyl, tert-butyl, phenyl, methoxy, ethoxy or phenoxy.

Examples of the complexes containing two Lp groups are compoundscorresponding to the formula:

wherein:

M is titanium, zirconium or hafnium, preferably zirconium or hafnium, inthe +2 or +4 formal oxidation state;

R³ in each occurrence independently is selected from the groupconsisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo andcombinations thereof, said R³ having up to 20 non-hydrogen atoms, oradjacent R³ groups together form a divalent derivative (that is, ahydrocarbadiyl, siladiyl or germadiyl group) thereby forming a fusedring system, and

X″ independently each occurrence is an anionic ligand group of up to 40non-hydrogen atoms, or two X″ groups together form a divalent anionicligand group of up to 40 non-hydrogen atoms or together are a conjugateddiene having from 4 to 30 non-hydrogen atoms forming a π-complex with M,whereupon M is in the +2 formal oxidation state, and

R*, E and x are as previously defined.

The foregoing metal complexes are especially suited for the preparationof polymers having stereoregular molecular structure. In such capacityit is preferred that the complex possesses C_(s) symmetry or possesses achiral, stereorigid structure. Examples of the first type are compoundspossessing different delocalized π-bonded systems, such as onecyclopentadienyl group and one fluorenyl group. Similar systems based onTi(IV) or Zr(IV) were disclosed for preparation of syndiotacfic olefinpolymers in Ewen, et al., J. Am. Chem. Soc. 110, 6255-6256 (1980).Examples of chiral structures include rac bis-indenyl complexes. Similarsystems based on Ti(IV) or Zr(IV) were disclosed for preparation ofisotactic olefin polymers in Wild et al., J. Organomet. Chem., 232,233-47, (1982).

Exemplary bridged ligands containing two π-bonded groups are:dimethylbis(cyclopentadienyl)silane,dimethylbis(tetramethylcyclopentadienyl)silane,dimethylbis(2-ethylcyclopentadien-1-yl)silane,dimethylbis(2-t-butylcyclopentadien-1-yl)silane,2,2-bis(tetramethylcyclopentadienyl)propane,dimethylbis(inden-1-yl)silane, dimethylbis(tetrahydroinden-1-yl)silane,dimethylbis(fluoren-1-yl)silane,dimethylbis(tetrahydrofluoren-1-yl)silane,dimethylbis(2-methyl4-phenylinden-1-yl)-silane,dimethylbis(2-methylinden-1-yl)silane,dimethyl(cyclopentadienyl)(fluoren-1-yl)silane,dimethyl(cyclopentadienyl)(octahydrofluoren-1-yl)silane,dimethyl(cyclopentadienyl)(tetrahydrofluoren-1-yl)silane,(1,1,2,2-tetramethy)-1,2-bis(cyclopentadienyl)disilane,(1,2-bis(cyclopentadienyl)ethane, anddimethyl(cyclopentadienyl)-1-(fluoren-1-yl)methane.

Preferred X″ groups are selected from hydride, hydrocarbyl, silyl,germyl, halohydrocarbyl, halosilyl, silylhydrocarbyl andaminohydrocarbyl groups, or two X″ groups together form a divalentderivative of a conjugated diene or else together they form a neutral,π-bonded, conjugated diene. Most preferred X″ groups are C₁₋₂₀hydrocarbyl groups.

A further class of metal complexes utilized in the present inventioncorresponds to the preceding formula Lp_(l)MX_(m)X′_(n)X″_(p), or adimer thereof, wherein X is a divalent substituent of up to 50non-hydrogen atoms that together with Lp forms a metallocycle with M.

Preferred divalent X substituents include groups containing up to 30non-hydrogen atoms comprising at least one atom that is oxygen, sulfur,boron or a member of Group 14 of the Periodic Table of the Elementsdirectly attached to the delocalized π-bonded group, and a differentatom, selected from the group consisting of nitrogen, phosphorus, oxygenor sulfur that is covalently bonded to M.

A preferred class of such Group 4 metal coordination complexes usedaccording to the present invention corresponds to the formula:

wherein:

M is titanium or zirconium, preferably titanium in the +2, +3, or +4formal oxidation state;

R³ in each occurrence independently is selected from the groupconsisting of hydrogen, hydrocarbyl, silyl, germyl, cyano, halo andcombinations thereof, said R³ having up to 20 non-hydrogen atoms, oradjacent R³ groups together form a divalent derivative (that is, ahydrocarbadiyl, siladiyl or germadiyl group) thereby forming a fusedring system,

each X″ is a halo, hydrocarbyl, hydrocarbyloxy or silyl group, saidgroup having up to 20 non-hydrogen atoms, or two X″ groups together forma neutral C₅₋₃₀ conjugated diene or a divalent derivative thereof;

Y is —O—, —S—, —NR*—, —PR*—; and

Z is SiR*₂, CR*₂, SiR*₂SiR*₂, CR*₂CR*₂, CR*═CR*, CR*₂SiR*₂, or GeR*₂,wherein R* is as previously defined.

Illustrative Group 4 metal complexes that may be employed in thepractice of the present invention include:

cyclopentadienyltitaniumtrimethyl,

cyclopentadienyltitaniumtriethyl,

cyclopentadienyltitaniumtriisopropyl,

cyclopentadienyltitaniumtriphenyl,

cyclopentadienyltitaniumtribenzyl,

cyclopentadienyltitanium-2,4-dimethylpentadienyl,

cyclopentadienyltitanium-2,4-dimethylpentadienyl•triethylphosphine,

cyclopentadienyltitanium-2,4-dimethylpentadienyl•trimethylphosphine,

cyclopentadienyltitaniumdimethylmethoxide,

cyclopentadienyltitaniumdimethylchloride,

pentamethylcyclopentadienyltitaniumtrimethyl,

indenyltitaniumtrimethyl,

indenyltitaniumtriethyl,

indenyltitaniumtripropyl,

indenyltitaniumtriphenyl,

tetrahydroindenyltitaniumtribenzyl,

pentamethylcyclopentadienyltitaniumtriisopropyl,

pentamethylcyclopentadienyltitaniumtribenzyl,

pentamethylcyclopentadienyltitaniumdimethylmethoxide,

pentamethylcyclopentadienyltitaniumdimethylchloride,

bis(η⁵-2,4-dimethylpentadienyl)titanium,

bis(η⁵-2,4-dimethylpentadienyl)titanium•trimethylphosphine,

bis(η⁵-2,4-dimethylpentadienyl)titanium•triethylphosphine,

octahydrofluorenyltitaniumtrimethyl,

tetrahydroindenyltitaniumtrimethyl,

tetrahydrofluorenyltitaniumtrimethyl,

(tert-butylamido)(1,1-dimethyl-2,3,4,9,10-η-1,4,5,6,7,8-hexahydronaphthalenyl)dimethylsilanetitaniumdimethyl,

(tert-butylamido)(1,1,2,3-tetramethyl-2,3,4,9,10-η-1,4,5,6,7,8-hexahydronaphthalenyl)dimethylsilanetitaniumdimethyl,

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium dibenzyl,

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium dimethyl,

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)-1,2-ethanediyltitaniumdimethyl,

(tert-butylamido)(tetramethyl-η⁵-indenyl)dimethylsilanetitaniumdimethyl,

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium (III) 2-(dimethyiamino)benzyl;

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium(III) allyl,

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium(III) 2,4-dimethylpentadienyl,

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium(II) 1,4-diphenyl-1,3-butadiene,

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium(II) 1,3-pentadiene,

(tert-butylamido)(2-methylindenyl)dimethylsiianetitanium (II)1,4diphenyl-1,3-butadiene,

(tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (II)2,4-hexadiene,

(tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV)2,3dimethyl-1,3-butadiene,

(tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV) isoprene,

(tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV)1,3-butadiene,

(tert-butylamido)(2,3-dimethylindenyl)dimethylslianetitanium (IV)2,3-dimethyl-1 ,3-butadiene,

(tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (IV)isoprene

(tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (IV)dimethyl

(tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (IV)dibenzyl

(tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (IV)1,3-butadiene,

(tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (II)1,3-pentadiene,

(tert-butylamido)(2,3-dimethylindenyl)dimethylsilanetitanium (II)1,4-diphenyl-1,3-butadiene,

(tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (II)1,3-pentadiene,

(tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV) dimethyl,

(tert-butylamido)(2-methylindenyl)dimethylsilanetitanium (IV) dibenzyl,

(tert-butylamido)(2-methyl-4-phenylindenyl)dimethylsilanetitanium (II)1,4-diphenyl-1,3-butadiene,

(tert-butylamido)(2-methyl-4-phenylindenyl)dimethylsilanetitanium (II)1,3-pentadiene,

(tert-butylamido)(2-methyl-4-phenylindenyl)dimethylsilanetitanium (II)2,4-hexadiene,

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethyl-silanetitanium(IV) 1,3-butadiene,

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium(IV) 2,3-dimethyl-1,3-butadiene,

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium(IV) isoprene,

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethyl-silanetitanium(II) 1,4-dibenzyl-1,3-butadiene,

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethylsilanetitanium(II) 2,4-hexadiene,

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienyl)dimethyl-silanetitanium(II) 3-methyl-1,3-pentadiene,

(tert-butylamido)(2,4-dimethylpentadien-3-yl)dimethylsilanetitaniumdimethyl,

(tert-butylamido)(6,6-dimethylcyclohexadienyl)dimethylsilanetitaniumdimethyl,

(tert-butylamido)(1,1-dimethyl-2,3,4,9,10-η-1,4,5,6,7,8-hexahydronaphthalen-4-yl)dimethylsilanetitaniumdimethyl,

(tert-butylamido)(1,1,2,3-tetramethyl-2,3,4,9,10-η-1,4,5,6,7,8-hexahydronaphthalen-4-yl)dimethylsilanetitaniumdimethyl

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienylmethylphenylsilanetitanium (IV) dimethyl,

(tert-butylamido)(tetramethyl-η⁵-cyclopentadienylmethylphenylsilanetitanium (II) 1,4-diphenyl-1,3-butadiene,

1-(tert-butylamido)-2-(tetramethyl-η⁵-cyclopentadienyi)ethanediyltitanium(IV) dimethyl, and

1-(tert-butylamido)-2-(tetramethyl-η⁵-cyclopentadienyl)ethanediyltitanium(II) 1,4-diphenyl-1,3-butadiene.

Complexes containing two Lp groups including bridged complexes suitablefor use in the present invention include:

bis(cyclopentadienyl)zirconiumdimethyl,

bis(cyclopentadienyl)zirconium dibenzyl,

bis(cyclopentadienyl)zirconium methyl benzyl,

bis(cyclopentadienyl)zirconium methyl phenyl,

bis(cyclopentadienyl)zirconiumdiphenyl,

bis(cyclopentadienyl)titanium-allyl,

bis(cyclopentadienyl)zirconiummethylmethoxide,

bis(cyclopentadienyl)zirconiummethylchloride,

bis(pentamethylcyclopentadienyl)zirconiumdimethyl,

bis(pentamethylcyclopentadienyl)titaniumdimethyl,

bis(indenyl)zirconiumdimethyl,

indenylfluorenylzirconiumdimethyl,

bis(indenyl)zirconiummethyl(2-(dimethylamino)benzyl),

bis(indenyl)zirconiummethyltrimethylsilyl,

bis(tetrahydroindenyl)zirconiummethyltrimethylsilyl,

bis(pentamethylcyclopentadienyl)zirconiummethylbenzyl,

bis(pentamethylcyclopentadienyl)zirconiumdibenzyl,

bis(pentamethylcyclopentadienyl)zirconiummethylmethoxide,

bis(pentamethylcyclopentadienyl)zirconiummethylchloride,

bis(methylethylcyclopentadienyl)zirconiumdimethyl,

bis(butylcydopentadienyl)zirconiumdibenzyl,

bis(t-butylcyclopentadienyl)zirconiumdimethyl,

bis(ethyltetramethylcyclopentadienyl)zirconiumdimethyl,

bis(methylpropylcyclopentadienyl)zirconiumdibenzyl,

bis(trimethylsilylcyclopentadienyl)zirconiumdibenzyl,

dimethylsilyl-bis(cyclopentadienyl)zirconiumdimethyl,

dimethylsilyl-bis(tetramethylcyclopentadienyl)titanium (III) allyl

dimethylsilyl-bis(t-butylcyclopentadienyl)zirconiumdichloride,

dimethylsilyl-bis(n-butylcyclopentadienyl)zirconiumdichloride,

(methylene-bis(tetramethylcyclopentadienyl)titanium(III)2-(dimethylamino)benzyl,

(methylene-bis(n-butylcyclopentadienyl)titanium(III)2-(dimethylamino)benzyl,

dimethylsilyl-bis(indenyl)zirconiumbenzylchloride,

dimethylsilyl-bis(2-methylindenyl)zirconiumdimethyl,

dimethylsilyl-bis(2-methyl-4-phenylindenyl)zirconiumdimethyl,

dimethylsilyl-bis(2-methylindenyl)zirconium-1,4-diphenyl-1,3-butadiene,

dimethylsilyl-bis(2-methyl-4-phenylindenyl)zirconium (11)1,4-diphenyl-1,3-butadiene,

dimethylsilyl-bis(tetrahydroindenyl)zirconium(II)1,4-diphenyl-1,3-butadiene,

dimethylsilyl-bis(fluorenyl)zirconiummethylchloride,

dimethylsilyl-bis(tetrahydrofluorenyl)zirconium bis(trimethylsilyl),

(isopropylidene)(cyclopentadienyl)(fluorenyl)zirconiumdibenzyl, and

dimethylsilyl(tetramethylcyclopentadienyl)(fluorenyl)zirconium dimethyl.

Other catalysts, especially catalysts containing other Group 4 metals,will, of course, be apparent to those skilled in the art.

The cocatalysts of the invention may also be used in combination with aan oligomeric or polymeric alumoxane compound, atri(hydrocarbyl)aluminum compound, adi(hydrocarbyl)(hydrocarbyloxy)aluminum compound, adi(hydrocarbyl)(dihydrocarbyl-amido)aluminum compound, abis(dihydrocarbylamido)(hydrocarbyl)aluminum compound, adi(hydrocarbyl)amido(disilyl)aluminum compound, adi(hydrocarbyl)-amido(hydrocarbyl)(silyl)aluminum compound, abis(dihydrocarbylamido)(silyl)aluminum compound, or a mixture of theforegoing compounds, having from 1 to 20 non-hydrogen atoms in eachhydrocarbyl, hydrocarbyloxy, or silyl group, if desired. These aluminumcompounds are usefully employed for their beneficial ability to scavengeimpurities such as oxygen, water, and aldehydes from the polymerizationmixture.

Preferred aluminum compounds include C₂₋₆ trialkyl aluminum compounds,especially those wherein the alkyl groups are ethyl, propyl, isopropyl,n-bulyl, isobutyl, pentyl, neopentyl, or isopentyl,dialkyl(aryloxy)aluminum compounds containing from 1-6 carbons in thealkyl group and from 6 to 18 carbons in the aryl group (especially(3,5-di(t-butyl)-4-methylphenoxy)diisobutylaluminum), methylalumoxane,modified methylalumoxane and diisobutylalumoxane. The molar ratio ofaluminum compound to metal complex is preferably from 1:10,000 to1000:1, more preferably from 1:5000 to 100:1, most preferably from 1:100to 100:1.

The molar ratio of catalyst/cocatalyst employed preferably ranges from10:1 to 1:10, more preferably from 2.1:1 to 1:1.5, most preferably from2.05:1 to 1:1. Mixtures of the activating cocatalysts of the presentinvention may also be employed if desired.

Suitable addition polymerizable monomers include ethylenicallyunsaturated monomers, acetylenic compounds, conjugated or non-conjugateddienes, and polyenes. Preferred monomers include olefins, for examplesalpha-olefins having from 2 to 20,000, preferably from 2 to 20, morepreferably from 2 to 8 carbon atoms and combinations of two or more ofsuch alphaolefins. Particularly suitable alpha-olefins include, forexample, ethylene, propylene, 1-butene, 1-pentene,4-methylpentene-1,1-hexene, 1-heptene, 1-octene, 1-nonene, 1-decene,1-undecene, 1-dodecene, 1-tridecene, 1-tetradecene, 1-pentadecene, orcombinations thereof, as well as long chain vinyl terminated oligomericor polymeric reaction products formed during the polymerization, andC₁₋₃₀ α-olefins specifically added to the reaction mixture in order toproduce relatively long chain branches in the resulting polymers.Preferably, the alpha-olefins are ethylene, propene, 1-butene,4-methyl-pentene-1,1-hexene, 1-octene, and combinations of ethyleneand/or propene with one or more of such other alpha-olefins. Otherpreferred monomers include styrene, halo- or alkyl substituted styrenes,tetrafluoroethylene, vinylcyclobutene, 1,4-hexadiene, dicyclopentadiene,ethylidene norbornene, and 1,7-octadiene. Mixtures of theabove-mentioned monomers may also be employed.

In general, the polymerization may be accomplished at conditions wellknown in the prior art for Ziegler-Natta or Kaminsky-Sinn typepolymerization reactions. Suspension, solution, slurry, gas phase orhigh pressure, whether employed in batch or continuous form or otherprocess conditions, may be employed if desired. Examples of such wellknown polymerization processes are depicted in WO 88/02009, U.S. Pat.Nos. 5,084,534, 5,405,922, 4,588,790, 5,032,652, 4,543,399, 4,564,647,4,522,987, and elsewhere. Preferred polymerization temperatures are from0-250° C. Preferred polymerization pressures are from atmospheric to3000 atmospheres.

Preferred processing conditions include solution polymerization, morepreferably continuous solution polymerization processes, conducted inthe presence of an aliphatic or alicyclic liquid diluent. By the term“continuous polymerization” is meant that at least the products of thepolymerization are continuously removed from the reaction mixture, suchas for example by devolatilization of a portion of the reaction mixture.Preferably one or more reactants are also continuously added to thepolymerization mixture during the polymerization. Examples of suitablealiphatic or alicyclic liquid diluents include straight andbranched-chain hydrocarbons such as isobutane, butane, pentane, hexane,heptane, octane, and mixtures thereof; alicyclic hydrocarbons such ascyclohexane, cydoheptane, methylcyclohexane, methylcycloheptane, andmixtures thereof; and perfluorinated hydrocarbons such as pertluorinatedC₄₋₁₀ alkanes. Suitable diluents also include aromatic hydrocarbons(particularly for use with aromatic α-olefins such as styrene or ringalkyl-substituted styrenes) including toluene, ethylbenzene or xylene,as well as liquid olefins (which may act as monomers or comonomers)including ethylene, propylene, butadiene, cyclopentene, 1-hexene,3-methyl-1-pentene, 4-methyl-1-pentene, 1,4-hexadiene, 1-octene,1-decene, styrene, divinylbenzene, allylbenzene, vinyltoluene (includingall isomers alone or in admixture). Mixtures of the foregoing are alsosuitable.

In most polymerization reactions the molar ratio ofcatalyst:polymerizable compounds employed is from 10⁻¹²:1 to 10⁻¹:1,more preferably from 10⁻¹²:1 to 10⁻⁵:1.

The catalyst composition of the invention may also be utilized incombination with at least one additional homogeneous or heterogeneouspolymerization catalyst in separate reactors connected in series or inparallel to prepare polymer blends having desirable properties. Anexample of such a process is disclosed in WO 94/00500, equivalent toU.S. Ser. No. 07/904,770 ABN. A more specific process is disclosed incopending application U.S. Ser. No. 08/10958, filed Jan. 29, 1993 ABN.

Molecular weight control agents can be used in combination with thepresent cocatalysts. Examples of such molecular weight control agentsinclude hydrogen, trialkyl aluminum compounds or other known chaintransfer agents. A particular benefit of the use of the presentcocatalysts is the ability (depending on reaction conditions) to producenarrow molecular weight distribution α-olefin homopolymers andcopolymers in greatly improved catalyst efficiencies. Preferred polymershave Mw/Mn of less than 2.5, more preferably less than 2.3. Such narrowmolecular weight distribution polymer products are highly desirable dueto improved tensile strength properties.

The catalyst composition of the present invention can also be employedto advantage in the gas phase polymerization and copolymerization ofolefins. Gas phase processes for the polymerization of olefins,especially the homopolymerization and copolymerization of ethylene andpropylene, and the copolymerization of ethylene with higher alphaolefins such as, for example, 1-butene, 1-hexene, 4-methyl-1-pentene arewell known in the art. Such processes are used commercially on a largescale for the manufacture of high density polyethylene (HDPE), mediumdensity polyethylene (MDPE), linear low density polyethylene (LLDPE) andpolypropylene.

The gas phase process employed can be, for example, of the type whichemploys a mechanically stirred bed or a gas fluidized bed as thepolymerization reaction zone. Preferred is the process wherein thepolymerization reaction is carried out in a vertical cylindricalpolymerization reactor containing a fluidized bed of polymer particlessupported above a perforated plate, the fluidisation grid, by a flow offluidisation gas.

The gas employed to fluidize the bed comprises the monomer or monomersto be polymerized, and also serves as a heat exchange medium to removethe heat of reaction from the bed. The hot gases emerge from the top ofthe reactor, normally via a tranquilization zone, also known as avelocity reduction zone, having a wider diameter than the fluidized bedand wherein fine particles entrained in the gas stream have anopportunity to gravitate back into the bed. It can also be advantageousto use a cyclone to remove ultra-fine particles from the hot gas stream.The gas is then normally recycled to the bed by means of a blower orcompressor and a one or more heat exchangers to strip the gas of theheat of polymerization.

A preferred method of cooling of the bed, in addition to the coolingprovided by the cooled recycle gas, is to feed a volatile liquid to thebed to provide an evaporative cooling effect. The volatile liquidemployed in this case can be, for example, a volatile inert liquid, forexample, a saturated hydrocarbon having 3 to 8, preferably 4 to 6,carbon atoms. In the case that the monomer or comonomer itself is avolatile liquid, or can be condensed to provide such a liquid this canbe suitably be fed to the bed to provide an evaporative cooling effect.Examples of olefin monomers which can be employed in this manner areolefins containing from 3 to eight, preferably from 3 to six carbonatoms. The volatile liquid evaporates in the hot fluidized bed to formgas which mixes with the fluidizing gas. If the volatile liquid is amonomer or comonomer, it will undergo some polymerization in the bed.The evaporated liquid then emerges from the reactor as part of the hotrecycle gas, and enters the compression/heat exchange part of therecycle loop. The recycle gas is cooled in the heat exchanger and, ifthe temperature to which the gas is cooled is below the dew point,liquid will precipitate from the gas. This liquid is desirably recycledcontinuously to the fluidized bed. It is possible to recycle theprecipitated liquid to the bed as liquid droplets carried in the recyclegas stream, as described, for example, in EP-A-89691, U.S. Pat. No.4,543,399, WO 94/25495 and U.S. Pat. No. 5,352,749. A particularlypreferred method of recycling the liquid to the bed is to separate theliquid from the recycle gas stream and to reinject this liquid directlyinto the bed, preferably using a method which generates fine droplets ofthe liquid within the bed. This type of process is described in WO94/28032.

The polymerization reaction occurring in the gas fluidized bed iscatalyzed by the continuous or semi-continuous addition of catalyst.[Such catalyst can be supported on an inorganic or organic supportmaterial if desired. The catalyst can also be subjected to aprepolymerization step, for example, by polymerizing a small quantity ofolefin monomer in a liquid inert diluent, to provide a catalystcomposite comprising catalyst particles embedded in olefin polymerparticles.

The polymer is produced directly in the fluidized bed by catalyzed(co)polymerization of the monomer(s) on the fluidized particles ofcatalyst, supported catalyst or prepolymer within the bed. Start-up ofthe polymerization reaction is achieved using a bed of preformed polymerparticles, which, preferably, is similar to the target polyolefin, andconditioning the bed by drying with inert gas or nitrogen prior tointroducing the catalyst, the monomer(s) and any other gases which it isdesired to have in the recycle gas stream, such as a diluent gas,hydrogen chain transfer agent, or an inert condensable gas whenoperating in gas phase condensing mode. The produced polymer isdischarged continuously or discontinuously from the fluidized bed asdesired, optionally exposed to a catalyst kill and optionallypelletized.

It is understood that the present invention is operable in the absenceof any component which has not been specifically disclosed. Thefollowing examples are provided in order to further illustrate theinvention and are not to be construed as limiting. Unless stated to thecontrary, all parts and percentages are expressed on a weight basis.

EXAMPLE 1 Preparation of(tetrafluoro-1,4-phenylene)-bis-(di(pentafluorophenyl)borane) ((C₆F₆)₂B—C₆F₄—B (C₆F₅)₂)

Into a thick-walled flask containing a J. Young valve, 1,4-C₆F₄(SnMe₃)₂(0.60 g, 1.26 mmol) and (C₆F₅)₂BCl (2.87 g, 7.56 mmol) were added.Toluene (40 mL) was added, the flask was evacuated to 0.1 torr, and theJ. Young valve was closed. The flask was heated at 140° C. for 72 h. Thesolvent was removed in vacuo, and the residue washed with pentane (4×20mL). The resulting light yellow solid was exposed to dynamic vacuum(10⁻⁵ torr) for 12 h, giving the desired product as a microcrystallinepale yellow solid (0.75 g, 71 percent).

¹⁹F NMR (CD₂Cl₂): δ −125.7 (br, 8F, ortho C₆F₅), −128.2 (br, 4F, C₆F₄),−141.1 (br, 4F, para C₆F₅), −159.1 (br, 8F, meta C₆F₅) ppm. MS (El, 6.3V): m/e 838 (M⁺, 100 percent).

Activation of Metal Complex

Combination of the diborane compound of Example 1 with the zirconocenebiscyclopentadienylzirconium dimethyl in CD₂Cl₂ at 25° C. in a 1:1 and a2:1 atomic ratio (Zr:B) gave two cationic reaction productscorresponding to the monoanionic salt (1) and the dianionic salt (2)derivatives according to the following scheme.

NMR data for 1: ¹H NMR (CD₂Cl₂): δ 6.39 (s, 10H), 0.68 (s, 3H), 0.31(br, 3H) ppm. ¹⁹F NMR (CD₂Cl₂): δ −127.5 (d, ³J_(FF)=21 Hz, 3F), −129.3(t, ³J_(FF)=18 Hz, 1F), −131.8 (m, 1F), −132.4 (m, 6F), −136.7 (s, 1F:),−144.8 (s, 1F), −159.0 (br, 1F), −160.0 (m, 4F), −163.8 (br, 2F), −164.2(t, ³J_(FF)=19 Hz, 3F).

NMR data for 2: ¹H NMR (CD₂Cl₂): δ 6.29 (s, 20H), 0.45 (br, 6H), 0.29(br, 6H) ppm. ¹⁹F NMR (CD₂Cl₂): δ −131.5 (d, ³J_(FF)=18 Hz, 8F, orthoC₆F₅), −142.8 (br, 4F, C₆F₅), −162.4 (br, 4F, para C₆F₅), −165.3 (br,8F, meta C₆F₅) ppm.

EXAMPLE 2 Preparation of(tetrafluoro-1,2-phenylene)-bis-(di(pentafluorophenyl)borane)

A) Preparation of [1,2-C₆F₄BCl]₂

Excess BCl₃ (ca. 5.0 g, 44 mmol) was condensed into a thick-walled flaskcontaining a J. Young valve and 1,2-C₆F₄(SnMe₃)₂ (5.3 g, 11.1 mmol), at−196° C. The flask was evacuated to 0.05 torr, and the J. Young valvewas closed. The reaction mixture was heated at 180° C. for 18 h. Theexcess BCl₃ was removed under dynamic vacuum, giving a slightly moist,beige solid. The product was extracted with pentane (3×20 mL), leavingbehind 65 percent of the Me₃SnCl byproduct. The remaining Me₃SnCl wassublimed away at 40° C./10⁻⁵ torr. The product was then sublimed at 90°C./10⁻⁵ torr, giving [1,2-C₆F₄BCl]₂ as a yellow solid (1.15 g, 53percent).

¹⁹F NMR (C₆D₆): δ −122.7 (m, 4F), −143.9 (m, 4F) ppm.

¹³C NMR (CDCl₃): δ 152.6 (d, ¹J_(CF)=262 Hz), 144.6 (d, ¹J_(CF)=260 Hz),122.8 (br, B-C) ppm. MS (El, 8.7 V) (percent intensity): 392 (16), 391(18), 390 (67), 389 (M⁺, 47), 388 (100), 387 (51), 342 (21), 318 (22),304 (28), 250 (25), 201 (30). Anal. Calcd for C₁₂F₈B₂Cl₂: C, 37.1; H,0.0. Found: C, 38.2; H. 0.3.

B) Preparation of [1,2-C₆F₄B(C₆F₅)]₂,

Into a thick-walled flask containing a J. Young valve, [1,2-C₆F₄BCl]₂(0.265 g, 0.68 mmol) and (C₆F₅)₂SnMe₂ (0.33 g, 0.68 mmol) were placed.Toluene (20 mL) was added, the flask was evacuated to 0.1 torr, and theJ. Young valve was closed. The reaction solution was heated to 140° C.for 72 h, giving a bright yellow solution. The solution was concentratedto 10 mL, and then heated to dissolve all solids. Slow cooling of thissolution to −78° C. gave 2 as light yellow crystals. This solid wasfound to contain a small amount of Me₂SnCl₂, which can be removed underdynamic vacuum (10⁻⁵ torr/12 h), giving the desired product,[1,2-C₆F₄B(C₆F₅)]₂, as a light yellow crystalline solid (0.35 g, 68percent). Alternatively, because of the sensitivity of the compound, thecrude reaction solution can be exposed to dynamic vacuum (10⁻⁵ torr) for12 h, giving the product in >95 percent purity, without the need forcrystallization.

¹⁹F NMR (d₈-toluene): δ −118.2 (br, 4F, ortho C₆F₄), −133.9 (dd,³J_(FF)=25.1 Hz; ⁴J_(FF)=7.9 Hz, 4F, ortho C₆F₅), −138.9 (m, 4F, metaC₆F₄), −152.1 (t, ³J_(FF)=21 Hz, 2F, para C₆F₅), −161.4 (ddd, ³J_(FF)=22Hz; ³J_(FF)=22 Hz, ⁵J_(FF)=7 Hz, 4F, meta C₆F₅) ppm.

¹³C NMR (CDCl₃): δ 156.1 (d, ¹J_(CF)=267 Hz), 145.9 (d, ¹J_(CF)=265 Hz),144.3 (d, ^(J) _(CF)=241 HZ), 141.6 (d, ¹J_(CF)=265 Hz), 137.6 (d,¹J_(CF)=253 Hz), 128.3 (br), 23.7 (br) ppm.

Crystal Data

C₂₄F₁₈B₂•(2C₇H₈); monoclinic, space group P2₁/c; a =22.836(4),b=0.846(3), c=13.767(3) Å; b=99.66(2)°; V=3361 (1) Å³; Z=4;d_(calcd)=1.652 g/cm³; at −120° C. The structure was solved by directmethods. Owing to the paucity of data, the fluorine atoms were refinedanisotropically and the remaining non-hydrogen atoms were refinedisotropically. Hydrogen atoms were included in “idealized” positions andnot refined. The final cycle of full-matrix least-squares refinement wasbased on 2042 observed reflections (l>3.00 σ(l)) and 324 variableparameters and converged (largest parameter shift was 0.12 times itsesd) with unweighted and weighted agreement factors of R=0.051 andR_(w)=0.039. For clarity of the crystallographic discussion, it shouldbe noted that there are two half molecules in the asymmetric unit, andconsequently there are two independent bond distances and angles foreach bond distancelangle of 2.

Activation of Metal Complexes

Combination of the diborane compound of Example 2 with the zirconocenebiscyclopentadienylzirconium dimethyl in CD₂Cl₂ at 25° C. in a 1:1 and a2:1 atomic ratio (Zr:B) gave two cationic reaction productscorresponding to the monoanionic salt (3) and the dianionic salt (4)derivatives according to the following scheme.

NMR data for 3: ¹⁹F (CD₂Cl₂, 25° C.): δ −123.1 (br, 2F), −132.4 (m, 3F),−134.0 (br, 2F), −134.8 (br, 1F), −145.0 (br, 2F), −155.4 (t, ³J_(FF)=21Hz, 1F), −158.9 (m, 2F), −160.0 (m, 1F), −161.8 (br, 1F), −162.5 (br,1F), −164.1 (br, t, ³J_(FF)=21 Hz, 2F) ppm.

¹H (CD₂Cl₂, 25° C.): δ 6.34 (s, 10H), 0.66 (s, 3H), 0.17 (br, 3H) ppm.

NMR data for 4: ¹⁹F (CD₂Cl₂, 25° C.): δ −132.7 (br, 2F, ortho C₆F₅),−134.7 (br, 4F, ortho C₆F₄), −136.4 (br, 2F, ortho C₆F₅), −161.6 (t,³J_(FF)=20 Hz, 2F, pare C₆F₅), −162.6 (d, ³J_(FF)=19 Hz, 4F, meta C₆F₄),−164.4 (br, 2F, meta C₆F₅), −165.4 (br, 2F, meta C₆F₅) ppm. ¹H (CD₂Cl₂,25° C.): 0 6.22 (s, 10H), 0.69 (s, 3H), 0.19 (br, 3H) ppm; a slightexcess of (C₅H₅)₂ZrMe₂ was present in this sample, and resonancesattributable to this compound are also present.

Polymerizations

A two liter stirred reactor was charged with 640 mL Isopar™ E solvent,and 150 g of propylene. Hydrogen (25 ml at 35 Δpsi, 0.2 ΔMPa) was addedas a molecular weight control agent. The reactor was heated to 70° C.The catalyst composition was prepared in a drybox by mixing together0.005M toluene solutions of(tbutylamido)dimethyl(η⁵-tetramethylcyclopentadienyl)titanium dimethylcatalyst, and the compounds of examples 1 or 2 to give atomic ratios ofB/Ti of 1:1 or 2:1. After a mixing time of 5 minutes the solutions werethen transferred to an addition loop and injected into the reactor. Thepolymerization was allowed to proceed for 10 minutes while maintainingthe reaction temperature at 70° C. The polymer solution was transferredfrom the reactor into a glass kettle and dried in a vacuum oven for 16hours at a maximum temperature of 120° C. Results are contained in Table1.

TABLE 1 reaction efficiency μmol cocatalyst time (Kg polymer/ runcatalyst (μmol) min. g polymer g Ti)  1* 6 FAB¹ (6) 10 29.7 103 2 0.75Ex. 2 (0.75) 10 70.9 1,974  3* 6 FAB¹ (6) 10 37.0 129 4 1.5 Ex. 2 (0.75)10 66.4 925 5 3 Ex. 1 (3) 18.5 29.7 207 6 6 Ex. 1 (3) 10 49.2 171 *notan example of the invention ¹tris(pentafluorophenyl)borane

What is claimed is:
 1. A compound corresponding to the formula:

wherein: R¹ and R² independently each occurrence are C₁₋₂₀ hydrocarbyl,halohydrocarbyl, or halocarbyl groups, and Ar^(f1)-Ar^(f2) incombination, independently each occurrence, is a divalentfluoro-substituted aromatic group of from 6 to 20 carbons.
 2. Thecompound of claim 1 corresponding to the formula:


3. A compound corresponding to the formula:

wherein: R¹ and R² independently each occurrence are C₁₋₂₀ hydrocarbyl,halohydrocarbyl, or halocarbyl groups, and when connected to anegatively charged boron atom, one R¹ additionally comprises a cationselected from the group consisting of protonated cations of Bronstedacids, ferrocenium cations, carbonium cations, silylium cations, Ag⁺,and cationic derivatives of a Group 3-10 metal complex and whenconnected to a negatively charged boron atom, one R² additionallycomprises a cation selected from the group consisting of protonatedcations of Bronsted acids, ferrocenium, carbonium cations, silyliumcations, Ag⁺, and cationic derivatives of a Group 3-10 metal complex;and an Ar^(f1) group and an Ar^(f2) group together form a C₆₋₂₀ divalentbridging group.
 4. A compound according to claim 3 corresponding to theformula:

wherein, L⁺ is a cation of a Bronsted acid, or a ferrocenium, carbonium,silylium, or Ag⁺ cation.
 5. A catalyst system for polymerization ofα-olefins comprising, in combination, a Group 4 metal complex and acompound according to any one of claims 1-4, or the reaction productthereof.
 6. A polymerization process comprising contacting one or moreα-olefins under polymerization conditions with a catalyst systemaccording to claim
 5. 7. A process according to claim 6 which is asolution polymerization.
 8. A polymerization process according to claim7 that is a continuous solution polymerization.
 9. A polymerizationprocess according to claim 6 that is a gas phase polymerization.
 10. Thecompound of claim 4 wherein L⁺ is HN⁺R₃ where R is C₁₋₅₀ hydrocarbyl.11. The compound of claim 10 wherein one or two R groups are C₁₄₋₅₀aliphatic groups and the remaining R groups or group is C₁₋₄ aliphatic.12. The catalyst system of claim 5 wherein the Group 4 metal complexcorresponds to the formula:

wherein: M is titanium in the +4 formal oxidation state; R³ in eachoccurrence independently is selected from the group consisting ofhydrogen, hydrocarbyl, silyl, germyl, cyano, halo and combinationsthereof, said R³ having up to 20 non-hydrogen atoms, or adjacent R³groups together form a divalent derivative thereby forming a fused ringsystem, each X″ is a halo, hydrocarbyl, hydrocarbyloxy or silyl group,said group having up to 20 non-hydrogen atoms, or two X″ groups togetherform a divalent derivative of a C₅₋₃₀ conjugated diene; Y is —O—, —S—,—NR*—, —PR*—; and Z is SiR*₂, CR*₂, SiR*₂SiR*₂, CR*₂CR*₂, CR*═CR*,CR*₂SiR*₂, or GeR*₂, wherein R* is hydrogen or a group selected fromsilyl, hydrocarbyl, hydrocarbyloxy and combinations thereof, said R*having up to 30 carbon or silicon atoms.
 13. A catalyst system forpolymerization of α-olefins comprising, the combination or reactionproduct of a Group 4 metal complex corresponding to the formula:

wherein: M is titanium in the +4 formal oxidation state; R³ in eachoccurrence independently is selected from the group consisting ofhydrogen, hydrocarbyl, silyl, germyl, cyano, halo and combinationsthereof, said R³ having up to 20 non-hydrogen atoms, or adjacent R³groups together form a divalent derivative thereby forming a fused ringsystem, each X″ is a halo, hydrocarbyl, hydrocarbyloxy or silyl group,said group having up to 20 non-hydrogen atoms, or two X″ groups togetherform a divalent derivative of a C₅₋₃₀ conjugated diene; Y is —O—, —S—,—NR*—, —PR*—; and Z is SiR*₂, CR*₂, SiR*₂SiR*₂, CR*₂CR*₂, CR*═CR*,CR*₂SiR*₂, or GeR*₂, wherein R* is hydrogen or a group selected fromsilyl, hydrocarbyl, hydrocarbyloxy and combinations thereof, said R*having up to 30 carbon or silicon atoms, and a compound corresponding tothe formula:

 wherein: R¹ and R² independently each occurrence are C₁₋₂₀ hydrocarbyl,halohydrocarbyl, or halocarbyl groups, and when connected to anegatively charged boron atom, one R¹ additionally comprises a cationselected from the group consisting of protonated cations of Bronstedacids, ferrocenium cations, carbonium cations, silylium cations, Ag⁺,and cationic derivatives of a Group 3-10 metal complex and whenconnected to a negatively charged boron atom, one R² additionallycomprises a cation selected from the group consisting of protonatedcations of Bronsted acids, ferrocenium, carbonium cations, silyliumcations, Ag⁺, and cationic derivatives of a Group 3-10 metal complex;and an Ar^(f1) group and an Ar^(f2) group together form a C₆₋₂₀ divalentbridging group.
 14. A catalyst system for polymerization of α-olefinscomprising, the combination or reaction product of a Group 4 metalcomplex corresponding to the formula:

wherein: M is titanium in the +2 formal oxidation state; R³ in eachoccurrence independently is selected from the group consisting ofhydrogen, hydrocarbyl, silyl, germyl, cyano, halo and combinationsthereof, said R³ having up to 20 non-hydrogen atoms, or adjacent R³groups together form a divalent derivative thereby forming a fused ringsystem, two X″ groups together form a neutral C₅₋₃₀ conjugated diene; Yis —O—, —S—, —NR*—, —PR*—; and Z is SiR*₂, CR*₂, SiR*₂SiR*₂, CR*₂CR*₂,CR*═CR*, CR*₂SiR*₂, or GeR*₂, wherein R* is hydrogen or a group selectedfrom silyl, hydrocarbyl, hydrocarbyloxy and combinations thereof, saidR* having up to 30 carbon or silicon atoms, and a compound correspondingto the formula:

 wherein: R¹ and R² independently each occurrence are C₁₋₂₀ hydrocarbyl,halohydrocarbyl, or halocarbyl groups, and Ar^(f1)-Ar^(f2) incombination, independently each occurrence, is a divalentfluoro-substituted aromatic group of from 6 to 20 carbons.
 15. Acatalyst system for polymerization of α-olefins comprising, thecombination or reaction product of a Group 4 metal complex correspondingto the formula:

wherein: M is titanium in the +2 formal oxidation state; R³ in eachoccurrence independently is selected from the group consisting ofhydrogen, hydrocarbyl, silyl, germyl, cyano, halo and combinationsthereof, said R³ having up to 20 non-hydrogen atoms, or adjacent R³groups together form a divalent derivative thereby forming a fused ringsystem, two X″ groups together form a neutral C₅₋₃₀ conjugated diene; Yis —O—, —S—, —NR*—, —PR*—; and Z is SiR*₂, CR*₂, SiR*₂SiR*₂, CR*₂CR*₂,CR*═CR*, CR*₂SiR*₂, or GeR*₂, wherein R* is hydrogen or a group selectedfrom silyl, hydrocarbyl, hydrocarbyloxy and combinations thereof, saidR* having up to 30 carbon or silicon atoms, and a compound correspondingto the formula:

 wherein: R₁ and R² independently each occurrence are C₁₋₂₀ hydrocarbyl,halohydrocarbyl, or halocarbyl groups, and when connected to anegatively charged boron atom, one R₁ additionally comprises a cationselected from the group consisting of protonated cations of Bronstedacids, ferrocenium cations, carbonium cations, silylium cations, Ag⁺,and cationic derivatives of a Group 3-10 metal complex and whenconnected to a negatively charged boron atom, one R² additionallycomprises a cation selected from the group consisting of protonatedcations of Bronsted acids, ferrocenium, carbonium cations, silyliumcations, Ag⁺, and cationic derivatives of a Group 3-10 metal complex;and an Ar^(f1) group and an Ar^(f2) group together form a C₆₋₂₀ divalentbridging group.